Assigwos to metropolitan



Feb. 5, 1929. 7 wmw C. H. SPANGLER ELECTRIC POTENTIAL DETECTOR FiledDec. 12, 1925 ffiiifii H $577. 5]:

-I N VEN TOR.

A TTORIYEYS.

Patented Feb. 5, 1229.

entree stares arcane PATENT QFFEQEE,

CHARLES H. SPANGLER, E READING, PENNSYLVANIA, ASSIGNOR T0 METROPOLITANEDISON CO., 033 READING, PENNSYLVANIA, A GORPOPt-ATIQN OF PENNSYLVANIA.

ELECTRIC-PQTENTIAL DETECTOR.

Application filed December 12, 1925.

My invention relates to portable testing devices for safely andharmlessly determining the presence of an electric potential, and itconsists more particularly in. an improved casing therefor for safeoperation and for rendering readily visible the rays of a luminousdetector tube carried thereby, as

hereinafter more fully set forth in connec- A common type of suchdetector luminous tube is shown in the drawings, dotted lines 25 5indicating the sealed tube of gas, enclosed in the insulating cover 6,which latter has sight apertures or windows 7 to see the en closed tube,and an end contact 8, which latter when set against a wire or like sus-30 pected conductor, will indicate the presence of an electric potentialby making luminous the tube of gas, as visible through aperture 7 Suchknown type of detector testing device is adequately safe for lowvoltages. but requires dangerously close approach for high voltagetests; and the main object of my invention is to provide a safetymounting for such old detectortube to adapt itfor safe and harmless usewith the latter.

l Vith this main objectin view, I employ a carrier casing 10, ofnon-conductive material and preferably tubular in form, as shown, and oflarge diameter so as to spacedly surround the detector tube cover 6which it carries longitudinally disposed within its length. One end ofsaid casing is preferably closed, as shown, by a disc of glass 11, orthe like, retained by a spring ring 12, to form a dust proof windowaperture. The opposite casing end is provided with an end closure 13, ofnon-conductive material and preferably conical in shape as shown, andformed with a central tube-cover receiving aperture 14 extending to aconduc- Serial No. 75,082.

tive contact end 15, against the inner end of which the tube contact 8may directly contact, but preferably a coiled spring 16 is interposed toprovide for longitudinal variation of said tube cover 6 in assemblingsaid contact end 15 merely forming a conductive extension to tubecontact 8.

The casing is shown provided with a handle 20, set into a block 21secured by screws 22. 22 to said casing, whereby the operator is enabledto make tests by engaging the casing contact while remaining at a safedistance; and in order that he may see the effect upon the detector tub5 without further approach, I provide a reflector 25 within said casingadapted to intensifying and displayingly direct outwardly to makeclearly visible through the window 11, any luminous rays appearing inapertures 7. This reflector 25, as shown, closely fits within the casing10 and is secured as by a clamping bolt 26 to the tube cover 6 adjacentthe sight apertures 7 in the latter: and due to the preferred concaveshape of the reflector indicated, the luminous rays displayinglydirected through the window 11 are magnified so as to be more clearlyvisible.

To increase the efliciency of the detctor tube 5 for high voltages, Iprovide the easing 10, as shown, with an inner closely fitting sleeve 30of conductive material and extending longitudinally between the casingend closures, and electrically connect this by means of a conductor wire31 directly to tube end wire or to the usual capacity media commonlyemployed in well known manner within the tube cover 6, as setforth insaid Metzger patent; said wire, as shown, passing through the cover 6 incontact with said tube end wire or the capacity media therein contained,and held in place as by set screw 27. Such connecting wire 31 acts tosupport and carry the tube 6 within the casing 10, and also conductinglyadds the sleeve 30 as capacity media to the gas tube 5. My mountingdevice thus fully described, adapts the known luminous tube 5 for safedistance use, through the handle 10, for testing high voltage potential:and by means of the reflector 25 permits the operator to observe from adistance the reflected luminous rays passing through the tube apertures7, by intensifying and divertingly direct them outwardly through thecasing window 11.

The preferred construction shown and described may of course be changedto adapt it to the particular type of luminous tube employed, andotherwise modified within the spirit of the invention as defined in theclaims.

What I claim is:

1. In combination with a luminous potential detector comprising agas-filled tube with a windowed cover; a safety mounting thereforcomprising an insulating carrier casing with reflector means toangularly deflect any luminous rays appearing in said cover window forvision from outside said casing.

2. In combination with a luminous potential detector comprising agas-filled tube with a windowed cover; a safety mounting thereforcomprising an insulating carrier casing with reflector means tointensify and angularly deflect any luminous rays appearing in saidcover window for vision from outside said casing.

3. In combination with a luminous potential detector comprising agas-filled tube with. a windowed cover and an exterior contact; a safetymounting therefor comprising an insulating tubular casing to axiallysupport said detector in spaced relation within said casing, comprisingan insulating end closure 39 for the latter having a projecting contactin conductive engagement with said detector contact, and an annularreflector within said casing arranged to axially deflect any luminousrays appearing in said cover window.

4. In combination with a luminous potential detector comprising agas-filled tube with a windowed cover and an exterior contact; asafety-mounting for said detector comprising a tubular insulating casingh aving an interior capacity media sleeve, means within said casing toaxially support said detector, comprising an end closure having aprojecting contact conductively engaging one end of said tube, aconductive support connecting said sleeve to the opposite end of saidtube, and an annular interior reflector arranged to axially deflect anyluminous rays appearing in said cover window.

5. A luminous potential-detector safety mounting comprising anon-conductive casing having a conductive inner lining an interiorsupport for one end of said detector conductively connecting one end ofthe latter to said lining, an opposite detector end non-conductivesupport having a conductive detector end contact extension, and aninterior annular reflector arranged to axially deflect any luminous raysof said detector.

In testimony whereof I affix my signature.

CHARLES H. SPANGLER.

